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For this test, look for groups of points moving up or down in succession. Count consecutive points, including horizontal runs within the run. This pattern is probably the result of a trend in one of the system resources. The chart below shows a group of seven points moving downward.
See also: >> Analyze for special causes of variation >> Any point lying outside the control limits >> 7 or more points in a row above or below the centerline >> Any nonrandom pattern